Copter: remove unused crosstrack variables and parameters

Cross track is still calculated internally to the wpnav controller so we
should move this to a library and still report it to the ground station

ArduCopter/ArduCopter.pde

@@ -692,8 +692,6 @@ static struct   Location guided_WP;
 // deg * 100, The original angle to the next_WP when the next_WP was set
 // Also used to check when we pass a WP
 static int32_t original_wp_bearing;
-// The amount of angle correction applied to wp_bearing to bring the copter back on its optimum path
-static int16_t crosstrack_error;
 
 
 ////////////////////////////////////////////////////////////////////////////////

ArduCopter/GCS_Mavlink.pde

@@ -275,7 +275,7 @@ static void NOINLINE send_nav_controller_output(mavlink_channel_t chan)
         wp_distance / 1.0e2f,
         altitude_error / 1.0e2f,
         0,
-        crosstrack_error);      // was 0
+        0);
 }
 
 static void NOINLINE send_ahrs(mavlink_channel_t chan)

ArduCopter/Parameters.h

@@ -75,7 +75,7 @@ public:
                                                         // Yaw Rate 1 = fast,
                                                         // 2 = med, 3 = slow
 
-        k_param_crosstrack_min_distance,
+        k_param_crosstrack_min_distance,	// deprecated - remove with next eeprom number change
         k_param_rssi_pin,
         k_param_throttle_accel_enabled,
         k_param_yaw_override_behaviour,
@@ -145,7 +145,7 @@ public:
         // 160: Navigation parameters
         //
         k_param_rtl_altitude = 160,
-        k_param_crosstrack_gain,
+        k_param_crosstrack_gain,	// deprecated - remove with next eeprom number change
         k_param_rtl_loiter_time,
         k_param_rtl_alt_final,
         k_param_tilt_comp, //164
@@ -291,8 +291,6 @@ public:
     AP_Int16        waypoint_radius;
     AP_Int16        circle_radius;
     AP_Int16        waypoint_speed_max;
-    AP_Float        crosstrack_gain;
-    AP_Int16 		crosstrack_min_distance;
     AP_Int32        rtl_loiter_time;
     AP_Int16        land_speed;
     AP_Int16        auto_velocity_z_min;         // minimum vertical velocity (i.e. maximum descent) the autopilot may request

ArduCopter/Parameters.pde

@@ -235,22 +235,6 @@ const AP_Param::Info var_info[] PROGMEM = {
     // @User: Standard
     GSCALAR(waypoint_speed_max,     "WP_SPEED_MAX", WAYPOINT_SPEED_MAX),
 
-	// @Param: XTRK_GAIN_SC
-    // @DisplayName: Cross-Track Gain
-    // @Description: This controls the rate that the Auto Controller will attempt to return original track
-    // @Units: Dimensionless
-	// @User: Standard
-    GSCALAR(crosstrack_gain,        "XTRK_GAIN_SC", CROSSTRACK_GAIN),
-
-    // @Param: XTRK_MIN_DIST
-    // @DisplayName: Crosstrack mininum distance
-    // @Description: Minimum distance in meters between waypoints to do crosstrack correction.
-    // @Units: Meters
-    // @Range: 0 32767
-    // @Increment: 1
-    // @User: Standard
-    GSCALAR(crosstrack_min_distance, "XTRK_MIN_DIST",  CROSSTRACK_MIN_DISTANCE),
-
     // @Param: RTL_LOIT_TIME
     // @DisplayName: RTL loiter time
     // @Description: Time (in milliseconds) to loiter above home before begining final descent

ArduCopter/navigation.pde

@@ -262,9 +262,6 @@ static void verify_altitude()
 // Keeps old data out of our calculation / logs
 static void reset_nav_params(void)
 {
-    // We must be heading to a new WP, so XTrack must be 0
-    crosstrack_error                = 0;
-
     // Will be set by new command
     wp_bearing                      = 0;